I can account to the claim that it has use in endgame, mostly savage right now at this point. I but one of the few, if not only, that doesn't see this ability as an "oh shit" desperation ability.

You have to be aware that you'll be needing to use more than 3 aetherflow abilities in less than the minute it takes Aetherflow to come off of cool down. That's basically all it's good for in terms of healing.

Everything else about this skill is negligible until you try to apply it's use in content you really shouldn't need it in where it becomes detrimental.